Re: Buidling for am335x_evm

[Denys Dmytriyenko <denys@ti.com>]

On Sat, Oct 05, 2013 at 09:46:29AM -0700, Rudolf Streif wrote:
> Hi Denys,
> 
> I guess I have to follow up on this. Everything builds now and with
> core-image-base the kernel image is installed into /boot. The fdt is not
> however.

If you are finally getting the kernel image into /boot directory, but not the 
device trees, then you probably are not using the latest enough snapshot of 
meta-ti...


> I used the Beaglebone in this case because it's a known board to
> me and I have been able to boot it successfully with my own Beaglebone BSP
> many time.
> 
> This is what I did on a preformatted SD card with partition 0 with FAT and
> partition 1 with ext4 with the images built using the meta-ti layer:
> 
>    1. sudo cp MLO-beaglebone /run/media/rudi/BEAGBOOT/MLO
>    2. sudo cp u-boot-beaglebone.img /run/media/rudi/BEAGBOOT/u-boot.img
>    3. sudo tar x -C /run/media/rudi/beagroot1/ -f
>    core-image-base-beaglebone.tar.gz
>    4. sudo tar x -C /run/media/rudi/beagroot1/ -f
>    modules--3.11+3.12-rc3-r19a+gitrAUTOINC+f7579525de9f1d6086c407a6980f4f1c1c574256-beaglebone-20131005020051.tgz
>    5. cp uImage-am335x-bone.dtb
>    /run/media/rudi/beagroot1/boot/am335x-bone.dtb
> 
> For step 5 one of course has to know that the u-boot environment expects an
> fdt with the name am335x-bone.dtb in /boot.
> 
> The u-boot bootcmd is set to
> 
> bootcmd=run findfdt; run mmcboot;setenv mmcdev 1; setenv bootpart 1:2; run
> mmcboot;run nandboot;
> 
> findfdt finds and sets the fdtfile variable correctly to am335x-bone.dtb.
> 
> mmcboot eventually runs mmcloados which is set to:
> 
> mmcloados=run mmcargs; if test ${boot_fdt} = yes || test ${boot_fdt} = try;
> then if run loadfdt; then bootm ${loadaddr} - ${fdtaddr}; else if test
> ${boot_fdt} = try; then bootm; else echo WARN: Cannot load the DT; fi; fi;
> else bootm; fi;
> 
> That's the default. It loads the fdt correctly but it never loads the
> kernel image. There is no command that executes loaduimage which is set to:
> 
> loaduimage=load mmc ${bootpart} ${loadaddr} ${bootdir}/${bootfile}
> 
> 
> Now, I executed all these steps manually and loaded the fdt and the kernel
> image, etc and eventually ran bootm. u-boots loads and decompresses the
> kernel and then it stops at "Starting kernel..." Probably a device tree
> issue.
> 
> 
> There are two issues:
> 
>    1. u-boot environment does not load the kernel image. I can get around
>    that.
>    2. Device tree does not seem to match the kernel image but that's only a
>    guess at this point.
> 
> Thanks,
> Rudi